[r=mpontillo][bug=][author=danilo] 1. Remove legacy region test setup and instead make it part of the development settings to avoid problems due to differences in import order between Django 1.8 and 1.11.
2. Replace use of build_request_repr for the DebuggingLoggerMiddleware.
3. Stop restricting lookup types for JSONField and XMLField fields because this was of limited use and entirely changed in 1.10.